Khalifa Yehia, Broderick Alicia, Newberg John T
Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, United States of America.
J Phys Condens Matter. 2018 Aug 15;30(32):325001. doi: 10.1088/1361-648X/aad102. Epub 2018 Jul 4.
The ionic liquid-gas interface of 1-hexyl-3-methyl-imidazolium chloride, [HMIM][Cl], was examined in the presence of water vapor using lab-based ambient pressure x-ray photoelectron spectroscopy (APXPS) at room temperature. The interfacial water uptake was measured quantitatively in the pressure range of high vacuum up to a maximum of 5 Torr (27% RH) and back to high vacuum in a systematic manner. Water mole fractions in the interface determined from APXPS were compared to previously published tandem differential mobility analysis results on [HMIM][Cl] nanodroplets. Our findings show that water constitutes a significantly larger mole fraction at the interface when compared to the bulk. Additionally, the reverse isotherms showed that the uptake of water at the interface of [HMIM][Cl] is a reversible process.
在室温下，使用基于实验室的常压X射线光电子能谱（APXPS），在存在水蒸气的情况下，对1-己基-3-甲基咪唑鎓氯化物（[HMIM][Cl]）的离子液体-气体界面进行了研究。在高真空至最高5托（27%相对湿度）的压力范围内，以系统的方式定量测量了界面水吸收量，然后再回到高真空。将由APXPS确定的界面水摩尔分数与先前发表的关于[HMIM][Cl]纳米液滴的串联差分迁移率分析结果进行了比较。我们的研究结果表明，与本体相比，界面处水的摩尔分数要大得多。此外，反向等温线表明，[HMIM][Cl]界面处的水吸收是一个可逆过程。
